Mortality statistics represent important endpoints
in epidemiological studies. The diagnostic validity
of cerebral stroke and ischemic heart disease recorded as
the underlying cause of death in Norwegian mortality
statistics was assessed by using mortality data of participants
in the Bergen Clinical Blood Pressure Study in
Norway and autopsy records from the Gade Institute in
Bergen. In the 41 years of the study (1965–2005) 4,387
subjects had died and 1,140 (26%) had undergone a post
mortem examination; 548 (12%) died from cerebral stroke
and 1,120 (24%) from ischemic heart disease according to
the mortality statistics, compared to 113 (10%) strokes
and 323 (28%) coronary events registered in the autopsy
records. The sensitivity and positive predictive value of fatal cerebral strokes in the mortality statistics were 0.75,
95% confidence interval (CI) [0.66, 0.83] and 0.86 [0.77,
0.92], respectively, whereas those of coronary deaths were
0.87 [0.84, 0.91] and 0.85 [0.81, 0.89] respectively.
Cohen’s Kappa coefficients were 0.78 [0.72, 0.84] for
stroke and 0.80 [0.76, 0.84] for coronary deaths. In
addition to female gender and increasing age at death,
cerebral stroke was a negative predictor of an autopsy
being carried out (odds ratio (OR) 0.69, 95% CI [0.54,
0.87]), whereas death from coronary heart disease was not
(OR 1.14, 95% CI [0.97, 1,33]), both adjusted for gender
and age at death. There was substantial agreement
between mortality statistics and autopsy findings for both
fatal strokes and coronary deaths. Selection for post
mortem examinations was associated with age, gender and
cause of death.